Try washing the triflic acid out of your product?

According to the e-EROS, triflic acid is soluble in:

"water and in many polar organic solvents such

as DMF, sulfolane, DMSO, dimethyl sulfone, acetonitrile; sol

alcohols, ketones, ethers, and esters, but these generally are not

suitable inert solvents"

http://onlinelibrary.wiley.com/doi/10.1002/047084289X.rt246.pub2/pdf

Maybe you could triturate your crude using one of those solvent classes that your target compound won't dissolve in.

According to this source http://chemindustry.ru/Trifluoromethanesulfonic_Acid.php

triflic acid can dissolve in DCM so maybe try DCM or ether to begin with?

Distillation under reduced pressure...........in nitrogen atmosphere will solve the problem. As after distillation upto 80% of TfOH.......crystallisation could take place (with or without nonpolar solvents like Diethyl ether of petroleum ether.  

@ Andrew: Thanks for your comment. The reaction mixture contain mostly product and TfOH. I tried water extraction, but water act as weak base that cause most of the salt (product) decomposition. Also column (sillica gel or alumina) were not compatible. Most of the solvent mentioned above dissolved the product, so I have dificulties to remove TfOH.

@ Imran: Thanks for your comment. I also tried distillation and re-crystalization, which is effective. but distillation at temp 50-70 deg. is sometime substrate sensitive in my case. after distillation and  re-crystalization (4 times), product precipitated out as oily instead of solid, and in NMR there is two broad peak at 9.5 to 10 ppm with product peak. So, I think TfOH was not fully removed in this process.

You may consider bubbling nitrogen through the reaction media to remove TFA and follow it by a suitable column chromatography or  trituration. Most often trituration with ether followed by drying in warm vacuum oven helps to get sufficiently pure product.

Dear Khyarul,

after distillation of TfOH once again co-distill the remaining TfOH with toluene (or other distillable solvent above 120oC bp). The repetition of this process will definitely remove the trace TfOH. the oily nature could be due to hygroscopic nature of your product in addition TfOH is itself reactive to moisture. I think co-distillation immediately after the complete distillation of TfOH (upto 90%). Be particular for maintaining nitrogen atmosphere and dry condition.